Means for keeping open telltale holes of stay-bolts.



G. A. THOMAS.

MEANS FOR KEEPING EN TELLTALE HOLES 0F STAY BOLTS. APPLIOA FILED JUNE 29, 1914.

WITNESSES nuance.

PATENT :il

FFIQE.

CHARLES ALLEN THOMAS, 035 BIRMINGHAM, ALABAMA, ASSIGNOR F ONE-HALF TO F. A. MAYER, OF WASHINGTON, DISTRICTOF COLUMBIA.

MEANS FOR KEEPING OPEN TELLTALE HOLES OF STAY-BOLTS.

Specification of Letters Patent.

Patented Nov. 17, 1914..

Application filed June 29, 1914.. Serial No. 848,050.

To all whom it may concern Be it known that I, Crmnnns A. Tnotms, a citizen of the United States, residing at Birmingham, in the county of Jefferson and State of Alabama, have invented a new and useful Means for Keeping Open Telltale Holes of Stay-Bolts, of which the following is a specification.

This invention has reference to improvements in means for keeping the telltale holes of stay bolts open under conditions of use.

Under the law all stay bolts for boilers and the like must be drilled with holes not less than three-sixteenths of an inch in diameter and one and one-quarter inches deep, so that a defect such as a crack in the stay 1 bolt within the water or steam space of a boiler will become evident by leakage through the telltale hole.

Such holes, however, often become clogged so that their usefulness ends for the time being, and are only with diiiiculty cleaned out. When an inspector discovers such a condition the cleaning of the telltale holes is at once demanded, and this has been accomplished with considerable diificulty and loss of time.

It is the object of the present invention to provide means whereby the telltale holes may be kept efficiently clean with little trouble or expense.

For this purpose the invention comprises a foraminous or perforated sleeve fitting snugly in each hole and projecting from the open end thereof a suflicient distance to be readily grasped for removal, but holding its place under conditions of use by friction with the walls of the telltale hole. Such a sleeve may be made of wire cloth or perforated sheet metal wound into tubular form, and with each sleeve of a somewhat greater length than the depth of the hole to provide a projecting end by which the sleeve may be grasped for removal from the hole. The inner end of the sleeve may be inturned to facilitate its introduction into the hole, while the outer end may be folded back upon itself to reinforce the outer end against distortion.

The invention will be best understood from a consideration of the following detailed description, taken in connection with the accompanying drawings forming a part of this specification, with the further understanding that while the drawings show a practical form of the invention, the latter is not confined to any strict conformity with the showing of the drawings, but may be changed and modified so long as such changes and modifications mark no material departure from the salient features of the invention.

In the drawings :Figure l is a View of a stay bolt partly in section to show the application of the invention. Fig. 2 is a section on the line 22 of Fig. l but drawn on a larger scale. Fig. 3 is a perspective View of the sleeve employed but drawn on a larger scale than Fig. 1.

In Fig. 1 there are shown two plates 1, 2, which may be taken as indicative of boiler plates connected by stay bolts, one of which is shown at 3. The stay bolt extends through both plates in the particular showing of the drawings, and is suitably headed or riveted at the ends as shown at 4.

The stay bolt is indicated as provided with an axial telltale hole 5 entering one end of the bolt exterior to the respective boiler plate, and of a length to reach into the space between .the boiler plates, the minimum length of the hole as demanded by law being one and one-quarter inches, while the minimum diameter of the hole is three-size teenths of an inch. Of course, the telltale hole may be larger than this, depending upon the size of the stay bolt, and the thickness of the boiler plates. It is required that these telltale holes be kept clean so that any defect, such as a crack or the like in the stay bolt becomes at once apparent by the escape of water or steam at the outer end of the telltale hole. If, however, the hole be clogged up by an accumulation of material therein, as is liable to occur, the usefulness of the telltale hole as such is lost until the telltale hole is cleaned out. Under some circumstances the telltale holes may become wholly filled up, and the deposit may be quite hard, so that it is a matter of time and expense to clean out the holes. To avoid this the present invention provides a sleeve 6 shown in the drawings as made of a sheet of perforated metal bent into cylindrical form with the sleeve inturned at one end, as shown at 7, and outturned at the other end and folded back as shown at 8, while the sleeve so formed is sufficiently longer than the hole 5 to permit introduction thereinto for the full length of the hole with the returned or reinforced end 8 projecting be bent into tubular form there is a longitudinal split 9 in the tube by Which the desired elasticity of the tube may be brought about to hold it in the telltale hole With sufficient frictional engagement to prevent accidental displacement. The same effect may be brought about by the employment of any foraminous sheet of suitable material bent upon itself, and for the'purposes of the invention Wire netting or gauze made of Wire of suitable gage may be considered as equlvalent 1n practice to perforated sheet metal.

Should a defect arise in the stay bolt 3, which defect is sufliciently extensive to reach the telltale hole 5, the foraminous tube 6 gives free outlet to the Water or steam Which finds its way through the passages or perforations in the Walls of the tube to the interior of the tube, and from thence through the open outer end of the tube, If the sleeve 6 should become more or less clogged With accumulations it is easily removed and replaced by a clean sleeve, or cleaned out and telltale hole or bore.

By the present invention there is no necessity of laboriously digging out accumulations of material, Which are sometimes hard and tenacious, for should accumulations put back into the occur they lodge Within the-sleeve and the latter may be Withdrawn with the accumulations therein Without any especial effort. What is claimed is 1 l. A means for preventing clogging of telltale holes in stay bolts, comprising a foraminous sleeve introducible into and re movable from the telltale hole and of a size to beretained in the hole by frictional engagement With the Wall thereof.

2. A means for keeping open telltale holes with the inner end inturned and the outer end returned upon itself to there, form a reinforcement, the sleeve being 'of a length to have the reinforced end Wholly outside i a of the hole When the other end isseated against the inner end of the hole.

a. The combination with astay ing a telltale hole in one end, ofa removable sleeve adapted to said hole and comprising a sheet of foraminous material bent into tubular form With one end inturned but have and the other end returned upon itselflto f there form a reinforcement, the sleeve being longer than the depth of the hole to have thereinforced end exterior to the hole" When the inturned end is seated against the inner endof the hole.

In testimony, that I claim the foregoing as my own, I have hereto afliXed my signa-f ture in the presence of tWo Witnesses.

CHARLES ALLEN THOMAS. \Vitnesses: j

G. M. Tnisorr, O. A. WILTSIE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

' Washington, D. G. 1 

